Refillable cartridge fuse



Jan. 16, 1923.

1,442,153. J. w. JOHNSTON.

REFILLABLE CARTRIDGE FUSE.

FILED DEc.z2, 1919.

NVENTOR BY UF 7H /{ryma/L A TTORNE X Patented Jan. 16, 1923.

UNITED STATES JAMES W. JOHNSTON, OF SALT LAKE CITY, UTAH.

REFILLABLE CART RIDGE FUSE.

Application filed December 22, 1919.

lill

speciiication.

My invention relates to electric Ytuses, land has tor its oinect to provide an niciosed or cartridge fuse ot the rctillable type, which economical and simple in construction, easH ily and quickly assembled to replace a burned out fuse and whereby the electric contact is etiiciently secured by the gripping oi the end portions ot the Yfuse element when assembling the device.

rlfhese objects I accon'iplish with thev device illustrated in the accompanying drawings in which similar ietters and numera-is oi reference indicate like parts throughout the severai figures and as described in the speciticat-ion forming a part ot this application and pointed out in the appended claims.

In the drawings in whith I have shown a substantial embodiment ot' my invention, Figure 1 is a longitijidinal section of the device. Figure Q an end elevation ot my device with the jam collar and one ot the contact members removed Figure 3 is an end elevation 01"' my device with the jam cap in place thereon. Figures 4 and 5 are an edge elevation and plan view respectively ot' one itorm oit the contact and gripping members.

My invention consists in the assembling and construction of the elements required to provide a cartridge for an inclosed fuse member which member may be quickly replaced when melted, and consists of a cylinder 1 made oi' insulating material and externally threaded at each end. Two diametrically opposed recesses 2 are cut in each end oi said cylinder. An internally threaded sleeve 3 is screwed on each end of said cylinder and each has an externally thread ed portion 4 thereon with the end thereof partially closed by an inwardly turned flange 5. A recess G is cut in said flange 5 with a purpose to be hereafter explained, and in screwing said sleeves on said cylinder 1 the said recess G is to be positioned at right angles to said recesses 2 in the ends of said cylinder. Internally threaded jam collars 'i' are screwed on the externally threaded portion 4 ot said sleeves 3, and each has serial No. 346,693.

its end cut out to torni seat I provide coactir lars or caps 7. Each o.V .1 bers A has a shaped and be 2 oi the cylindi, and also engages in t" inneres 3, In the sai.. .:ontact aan said portions E) are made longer and e.: as gripiiing tinge il. The said iingers 1i are to be sli; pcd between 'the iaws ot' any knife connection as tern'iinais. (In the inner curved kside ot each oil said members A is provided the segment member 13, each ot which is gi ven the iiorm ot a segment ot a sphere and is to bear against the said tace or seat 8 oii the jam collars 7. The fuse member or link 14 which is used within the cartridge has its end portions firmly held between the pair oit' coacting contact members A and may take any ot the commonly used forms, and consists oi a strip ot easily melted inse material having one or more weakened portions adapted to melt when subjected to more than a predetermined amperage. In the end of each cone shaped segment 13 I provide ventiiating holes 10 opening to the interior ot the cartridge.

The assembling of my device is as tollows: The sleeves are screwed on the end portions of the insulating cylinder 1 with the portions 4 extended to receive the jam collars 7. The pair oi contact members A are then placed loosely in position, within the end of said portion 4, by engagingthe curved portion 9 in the respective recesses 2 and 6, and partially screwing one of said jam collars 7 on that end of my device, this will hold said Contact members A in place I then insert the fuse member 14 with one end portion between the pair of contact members 9 as shown in Figure 3 and then insert another one of said contact members A into the portion 4 of the other end of my device, as shown in Figure 2, and when the other of said contact members A is inserted at that end I screw on the other am collar 7 and tighten both of them. The tightening of said jam collars with their cone shaped u, Leg

faces 8 bearing against the segment members 13 will cause the contact members A to grip the end portions f the fuse member 14 irmly and without any tendency to twist the said fuse member 14. To refill the cartridge when the fuse member 14 is burned out I simply loosen each of said iam collars 7 and the parts of the burned ont fuse member 14% will fall out; and a new i'nember 14: may be easily and quickly placed in position and the said collars tightened or screwed up.

l thus provide a new and efficient cartii'idge inse within which the fuse member may be quickly placed and rigidly held by new and novel gripping members to make an electric safety inse without bending7 bolting or twisting the fuse member.

Having thus described my invention desire to secure by Letters Patent and claim:

l. A reillable cartridge fuse comprising a casing having recesses in its edges and ein ternal threads on each end portion; a fuse link carried in said |casing; a partial closure screwed on said threads of said easing and having a radially disposed slot in the end portion 0i each; contact memberswith asportion of each engaged in said recesses and slots; and jam collars'to canse said Contact members to grip the end portions of said fuse when screwed on said closure members.

a casing having recesses in its edges; a fuse link carried therein; a partial closure for each end 01' said casing and having a radially disposed slot in the end portions thereof; Contact members with portions engaged in said recesses and slots and adapted to be iorced toward each other to grip said fuse link; and means to force said Contact mem bers toward each other.

ln testimony whereof I have aiiiXed my signature.

JAMES W. JOHNSTON. 

